THE MOST important quality to look for when buying a plant, whether it is from a specialist nursery or a supermarket, is good health.

If the plant is damaged, faded, drooping or is losing its leaves – keep looking

If the plant is damaged, faded, drooping or is losing its leaves, keep looking until you find the glossy one with upright stems, new shoots and flower buds about to burst open.

But once you have got past these obvious requirements, what else should you be looking for when you buy new garden plants?

Tempting as it is to just buy whatever catches your eye, it is much more useful to make a list of what you need before you leave home.

That doesn’t mean you need to know the exact species to buy; but it’s good to have an idea of the colour you need to fit in with what is already in your garden, a shape and size that will complement a small or large garden, the texture that will make it stand out and to know whether you want something with fragrance – or not.

Size

This is probably the most important issue when choosing trees, because exotics like eucalyptus can grow nearly as tall as your house and natives like horse chestnut can have such huge canopies they block out the sun.

You should also consider how much shrubs can spread within a few years of being planted, and understand that you can fill in between shrubs with flowers while you’re waiting for them to grow.

Shape

Trees and shrubs in particular come in various shapes that you might want to avoid, or embrace.

Tempting as it is to just buy whatever catches your eye, it is much more useful to make a list of what you need before you leave home

For instance a prostrate-shaped shrub can be useful if you want something that won’t grow very tall but will spread itself out – but it will be useless if you want to block out the house that backs onto your garden.

Texture

Once you know how big or small you want your shrubs or trees to be, texture becomes the next consideration.

You’ll find differences in the texture of bark: rough, smooth, shiny, coloured or just brown; and then there are the leaves.

A few plants with huge leaves in among the everyday-sized leaves gives your borders some texture, as do different shades of green and non-green leaves.

Leaves also come in many different shapes: oval, long and thin or jagged so there is plenty of opportunity to vary the overall texture of a border or casual hedge.

Colour

You don’t have to have a colour-coded planting plan, but it can make for a more relaxing garden if you choose a few connecting colours and plenty of evergreen plants.

Different shades of white, with grey or blue-green leaved plants is a well-known strategy, but you could also limit yourself to blues, purples and soft pinks or group yellow, orange and red plants together.

Fragrance

If your choice of plants are scented then that is an added bonus for most, but for some people it is the best reason for having a particular plant in your garden.

If you or your partner is partially sighted, for instance, you will enjoy your garden far more if there are fragrant flowers or leaves to brush up against.

Taking the time to write down a few of the things your garden requires before going to a garden centre is the horticultural equivalent of eating a meal before you go food shopping.

Luckily, though, you won’t break your diet if you avoid the café and stick to buying plants.